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copied!<p>Mixing the file read operator (<code>< ... ></code>) with <code>getc</code> is a bad idea. It's not doing what you think it is.</p> <p>Try putting some debug output into the program to see what's going on. I tested the program by running it on itself (<code>./getc getc</code>).</p> <p>At the start of the <code>while</code> loop, the <code><INPUT></code> reads a line from your file and stores it in <code>$_</code>. You then use <code>getc</code> to read the next character from the file. That will be the first character from the second line of your file (probably a newline character - which is likely to be the only character on that line).</p> <p>The next time round the loop, the <code><INPUT></code> reads the next line of input. That's the <code>use strict</code> line. The <code>getc</code> reads the next character which is the 'u' from <code>use warnings</code>.</p> <p>And so it continues to the end of the file. The <code><INPUT></code> reads a line and then the <code>getc</code> reads the first character from the next line.</p> <p>That's not what you want at all. If you want to read a character at a time then you just need the <code>getc</code>.</p> <pre><code>#!/usr/bin/perl use strict; use warnings; my $input = shift; open(my $file, '<', $input); while (defined(my $c = getc $file)) { print "$c\n"; } </code></pre> <p>Another alternative would be to just use <code>< ... ></code> and split each line as you read it.</p> <pre><code>#!/usr/bin/perl use strict; use warnings; my $input = shift; open(my $file, '<', $input); while (<$file>) { foreach my $c (split //) { print "$c\n"; } } </code></pre> <p>But mixing the two approached is never going to work.</p>

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